It's not plastic. It's much smaller than the other treasure craft tiki mug (about half the size) and it has Original Kona Coffee Mill design on the back, not the tapa design. Also, the handle is on the opposite side of it's larger clone. This mug is very similar to the plastic Kona Coffee mug, but it is slightly smaller, a lighter shade of brown, and has a slightly different handle shape.

This brown ceramic mug was manufactured by Treasure Craft for the Kona Coffee Mill in Hawaii. This coffee company began producing their line in 1969. The mug has a scene from the mill on the back with the words "Original Kona Coffee Mill" above it. There was a similar plastic version made later with a more elongated handle and rougher details.